Make compiler tests independent of VM indexes (#2676)

The compiler unit tests do this:

```rust
assert_compiles(Program {
    source: r#"
        function main() -> int {
            let arr = [1, 2, 3];
            arr.length()
        }
    "#,
    expected: vec![(
        "main",
        vec![
            Instruction::LoadConst(0), // Index of the constant in the pool
            Instruction::LoadConst(1), // Index of the constant in the pool
            Instruction::LoadConst(2), // Index of the constant in the pool
            Instruction::AllocArray(3),
            Instruction::LoadGlobal(GlobalIndex::from_raw(50)), // Index of the function
            Instruction::LoadVar(1), // Index of the variable
            Instruction::Call(1),
            Instruction::Return,
        ],
    )],
})
```

Depending on specific object indexes is bad because if we add new
builtins they change. Also `LoadConst(0)` or `LoadVar(5)` is not very
readable, so instead we want:

```diff
assert_compiles(Program {
    source: r#"
        function main() -> int {
            let arr = [1, 2, 3];
            arr.length()
        }
    "#,
    expected: vec![(
        "main",
        vec![
-           Instruction::LoadConst(0), // Index of the constant in the pool
+           Instruction::LoadConst(Value::Int(1)),
-           Instruction::LoadConst(1), // Index of the constant in the pool
+           Instruction::LoadConst(Value::Int(2)),
-           Instruction::LoadConst(2), // Index of the constant in the pool
+           Instruction::LoadConst(Value::Int(3)),
            Instruction::AllocArray(3),
-           Instruction::LoadGlobal(GlobalIndex::from_raw(50)), // Index of the function
+           Instruction::LoadGlobal(Value::function("baml.Array.length")),
-           Instruction::LoadVar(1), // Index of the variable
+           Instruction::LoadVar("arr".to_string()),
            Instruction::Call(1),
            Instruction::Return,
        ],
    )],
})
```

Author: antoniosarosi

engine/baml-compiler/tests/arrays.rs

@@ -1,6 +1,6 @@
 //! Compiler tests for array construction.
 
-use baml_vm::Instruction;
+use baml_vm::test::{Instruction, Value};
 
 mod common;
 use common::{assert_compiles, Program};
@@ -17,11 +17,11 @@ fn array_constructor() -> anyhow::Result<()> {
         expected: vec![(
             "main",
             vec![
-                Instruction::LoadConst(0),
-                Instruction::LoadConst(1),
-                Instruction::LoadConst(2),
+                Instruction::LoadConst(Value::Int(1)),
+                Instruction::LoadConst(Value::Int(2)),
+                Instruction::LoadConst(Value::Int(3)),
                 Instruction::AllocArray(3),
-                Instruction::LoadVar(1),
+                Instruction::LoadVar("a".to_string()),
                 Instruction::Return,
             ],
         )],

engine/baml-compiler/tests/assertions.rs

@@ -1,6 +1,9 @@
 //! Compiler tests for assert statements.
 
-use baml_vm::{BinOp, CmpOp, Instruction};
+use baml_vm::{
+    test::{Instruction, Value},
+    BinOp, CmpOp,
+};
 
 mod common;
 use common::{assert_compiles, Program};
@@ -17,13 +20,13 @@ fn assert_statement_ok() -> anyhow::Result<()> {
         expected: vec![(
             "assertOk",
             vec![
-                Instruction::LoadConst(0), // 2
-                Instruction::LoadConst(1), // 2
+                Instruction::LoadConst(Value::Int(2)), // 2
+                Instruction::LoadConst(Value::Int(2)), // 2
                 Instruction::BinOp(BinOp::Add),
-                Instruction::LoadConst(2), // 4
+                Instruction::LoadConst(Value::Int(4)), // 4
                 Instruction::CmpOp(CmpOp::Eq),
                 Instruction::Assert,
-                Instruction::LoadConst(3), // 3
+                Instruction::LoadConst(Value::Int(3)), // 3
                 Instruction::Return,
             ],
         )],
@@ -42,11 +45,11 @@ fn assert_statement_not_ok() -> anyhow::Result<()> {
         expected: vec![(
             "assertNotOk",
             vec![
-                Instruction::LoadConst(0), // 3
-                Instruction::LoadConst(1), // 1
+                Instruction::LoadConst(Value::Int(3)), // 3
+                Instruction::LoadConst(Value::Int(1)), // 1
                 Instruction::CmpOp(CmpOp::Eq),
                 Instruction::Assert,
-                Instruction::LoadConst(2), // 2
+                Instruction::LoadConst(Value::Int(2)), // 2
                 Instruction::Return,
             ],
         )],

engine/baml-compiler/tests/builtins.rs

@@ -1,6 +1,6 @@
 //! Compiler tests for built-in method calls.
 
-use baml_vm::{GlobalIndex, Instruction, ObjectIndex};
+use baml_vm::test::{Instruction, Value};
 
 mod common;
 use common::{assert_compiles, Program};
@@ -17,12 +17,12 @@ fn builtin_method_call() -> anyhow::Result<()> {
         expected: vec![(
             "main",
             vec![
-                Instruction::LoadConst(0),
-                Instruction::LoadConst(1),
-                Instruction::LoadConst(2),
+                Instruction::LoadConst(Value::Int(1)),
+                Instruction::LoadConst(Value::Int(2)),
+                Instruction::LoadConst(Value::Int(3)),
                 Instruction::AllocArray(3),
-                Instruction::LoadGlobal(GlobalIndex::from_raw(5)),
-                Instruction::LoadVar(1),
+                Instruction::LoadGlobal(Value::function("baml.Array.length")),
+                Instruction::LoadVar("arr".to_string()),
                 // call with one argument (self)
                 Instruction::Call(1),
                 Instruction::Return,
@@ -49,9 +49,9 @@ fn fetch_as() -> anyhow::Result<()> {
         expected: vec![(
             "main",
             vec![
-                Instruction::LoadGlobal(GlobalIndex::from_raw(51)),
-                Instruction::LoadConst(0),
-                Instruction::LoadConst(1),
+                Instruction::LoadGlobal(Value::function("baml.fetch_as")),
+                Instruction::LoadConst(Value::string("https://dummyjson.com/todos/1")),
+                Instruction::LoadConst(Value::class("DummyJsonTodo")),
                 Instruction::DispatchFuture(2),
                 Instruction::Await,
                 Instruction::Return,
@@ -86,25 +86,26 @@ fn fetch_as_with_request_param() -> anyhow::Result<()> {
         expected: vec![(
             "main",
             vec![
-                Instruction::LoadGlobal(GlobalIndex::from_raw(51)),
-                Instruction::AllocInstance(ObjectIndex::from_raw(7)),
+                Instruction::LoadGlobal(Value::function("baml.fetch_as")),
+                Instruction::AllocInstance(Value::class("baml.HttpRequest")),
                 Instruction::Copy(0),
-                Instruction::LoadConst(0),
-                Instruction::AllocVariant(ObjectIndex::from_raw(10)),
+                Instruction::LoadConst(Value::Int(1)), // Enum variant index for Post
+                Instruction::AllocVariant(Value::enm("baml.HttpMethod")),
                 Instruction::StoreField(1),
                 Instruction::Copy(0),
-                Instruction::LoadConst(1),
+                Instruction::LoadConst(Value::string("https://dummyjson.com/todos/add")),
                 Instruction::StoreField(0),
                 Instruction::Copy(0),
-                Instruction::LoadConst(2),
-                Instruction::LoadConst(3),
-                Instruction::LoadConst(4),
-                Instruction::LoadConst(5),
-                Instruction::LoadConst(6),
-                Instruction::LoadConst(7),
+                // Map values first, then keys
+                Instruction::LoadConst(Value::string("Buy milk")),
+                Instruction::LoadConst(Value::Bool(false)),
+                Instruction::LoadConst(Value::Int(5)),
+                Instruction::LoadConst(Value::string("todo")),
+                Instruction::LoadConst(Value::string("completed")),
+                Instruction::LoadConst(Value::string("userId")),
                 Instruction::AllocMap(3),
                 Instruction::StoreField(4),
-                Instruction::LoadConst(8),
+                Instruction::LoadConst(Value::class("DummyJsonTodo")),
                 Instruction::DispatchFuture(2),
                 Instruction::Await,
                 Instruction::Return,